Dead-center device



July 30, 1929.

J. H. TOWERS DEAD CENTER DEVICE Filed. Aug. 17, 1927 INVENTOR. J

- TORNEY.

Patented July 30, 1929.

were rare;

JOHN H. 'rownns, or BALSAM LAKE, WISCONSIN.

DEAD-CENTER DEVICE.

Application filed August 17,1927. Serial No. 213,586.

The invention relates to an improved meinder 21 is provided with valve ports 22 and chanical movement designed to be employed for converting reciprocatory movement into movement of rotation, the object of the invention being to provide an assemblage of mechanical elements which will cooperate to overcome dead centers.

The invention is applicable for use in con nection with steam engines, gas engines, windmills, hand operated devices, or in any relation wherein it is desired to overcome dead centers.

An illustrative embodiment of the invention is shown in the accompanying drawings in which Figure l is a side view of the device shown connected at one end to a reciprocating piston, and at the other to a wheel.

Figure 2 is an end view of the same.

It is desired to transform the reciprocatory movement of the piston 3 into rotary movement of the wheel 4 by a suitable assemblage of mechanical elements which are so related that they eifectively overcome dead centers.

The piston 3 is mounted in its cylinder 4 and is provided with the usual piston rod 5, on the end of which is a sliding block 6 which is mounted to reciprocate in the slides 7 As will be seen in Figure 2, these slideways 7 are concave on their inner faces, while the top and bottom faces of the blocks 7 are correspondingly convex.

Slideways 8 are also secured to the support 9 below and parallel with the slideways 7. These slideways 8 are concave on their hearing face and the block 10 having convex upper and lower faces is formed to freely reciprocate between said slideways.

The block 10 has a fixed pivot 11 upon which the angle crank 12 is pivoted. One of the arms of the angle crank 12 is pivoted at 13 to the rotary element 4.

Intermediate its ends the other. arm of the angle crank is connected by means of the 23,one port extending into the cylinder near its top, and the other extending into the cylinder near its bottom. These ports are connected by means of the common pipe 2& into which a supply pipe leads.

N ow assuming that the mechanism is in v the position shown in full lines in Figure 1, and that compressed fluid is permitted to enter through the valve 22 into the cylinder 21 which causes the piston 20 to move downward thereby forcing the slide 16 to the position shown. Compressed fluidis per mitted to enter the cylinder 4 and move the piston 3 and associated parts to the right as indicated by dotted lines in Figure 1, thereby causing the wheel or rotary element 4 to rotate in a counter clockwise direction. The crank pin 13 is carried past the dead center position, due to the action of the pressure on the piston 20 which is operated at the point when the piston 3 begins its reverse stroke. One position which would normally be a dead center position, if the cylinder 21 and its associated'parts were absent, is indicated in the dotted lines, Figure 1, this being likewise the position in which the piston 3 has reached its extreme limit to the right and begins to reverse. However, when the piston 3 begins its reverse stroke the pivot 26 is being still forced to the right and the pivot 27 is being forced to the left causing the pivot 13 on the rotary element to snap past the dead center position. The same action occurs at the opposite position and the rotary member 4 continues to rotate uniformly in one direction, being carried past each dead center position by the action of the pressure cylinder 21 and its associated parts. On the reverse action, of course, it will be understood that the pressure is admitted through the valve 28 into the cylinder 21 and is admitted on the right hand side of the piston 3.

I am aware that certain changes may be made in the details of construction and relative arrangement of parts without departing from the spirit of my invention, and be within the scope of the appended claims.

What I claim is:

1. A device for overcoming dead centers, comprising a reciprocating block, a pivot thereon, a bell crank pivotally connected to said block on said pivot, a rotary element.

which the other arm of the crank is connected, and means acting to produce pressure upon the said block through the crank.

3. In a device for overcoming dead centers, a reciprocating block, a bell crank pivotally mounted on said block, a rotary element to which one arm of the crank is connected, a suitable source of power with which the other arm of the crankis connected, and means acting to produce pressure upon the said block through the crank, and means for reversing at will the direction of force of said means. I

4. In a device for overcoming dead centers, the combination with a reciprocating block, a pivot fixed on said block, an angle crank mounted at the juncture of its arms on said pivot, a rotary element pivotally connected to one of the arms of said crank, a source of power connected with the other armof said crank, and substantially at right angles thereto, and means for applying pressure to said crank to continue its movement to carry the pivotal connection between the rotary element and the crank over a dead center.

5. In a device for overcoming dead centers, an angle crank, a reciprocatory block, a fixed pivot on saidblock, said crank being pivotally mounted at the juncture of its arms on the fixed pivot, a rotary element pivotally connected to one arm of said crank, a piston connected with the other arm of said crank, and a pressure device also connected with said other arm of the crank.

6. In a device for overcoming dead centers, an angle crank, a reciprocatory block, a fixed pivot on said block, said crank being pivotally mounted at the juncture of its arms on the fixed pivot, a rotary element pivotally connected to one arm of said crank, a piston connected with the other arm of said crank, and 'a pressure device also connected with said other arm of the crank, and means to control the direction of movement of the pressure device. I

7. In a device for overcoming dead centers, a reciprocatory block, an angle crank pivotally connected to said block, a rotary element connected to one arm of said crank, a power piston, a link connecting the piston with the second arm of said crank intermediate its ends, and a pressure device connected to the end of the said second arm, and means to control the direction of movement of the pressure device.

In testimony whereof I affix my signature.

JOHN H. TOWERS. 

